Such a diaphragm valve is known from EP 0 897 076 A1. Said diaphragm valve is characterized in that in order to replace the diaphragm it is not required to disassemble the complete actuator. Rather, at first the upper part of the casing including the accommodated actuator therein has to be removed from the lower part of the casing which includes the valve seat. The diaphragm is screwed to a diaphragm support or coupled to a diaphragm support by using a bayonet connection. The diaphragm support includes an insertion groove by means of which the diaphragm support may be plugged onto a valve spindle. A pressure member is pushed on the diaphragm support which surrounds the diaphragm support and is adapted to press the complete area of the diaphragm against the valve seat, which normally extends in an arc shape. To this end, the pressure member has a convex shape on the front wall on the side of the diaphragm thereof and it may have a complementing shape corresponding to the valve seat. After plugging the diaphragm support onto the valve spindle, the pressure member which is made of plastics, is pushed up in order to secure the diaphragm support against a radial movement on the valve spindle.
The objective of the invention is to improve the known diaphragm valve in order to facilitate assembly and disassembly thereof. In addition, it is intended to fabricate the diaphragm valve in a more cost-efficient way.